Primary Information |
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| BoMiProt ID | Bomi162 |
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| Protein Name | Mucin 1 |
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| Organism | Bos taurus |
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| Uniprot ID | Q8WML4 |
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| Milk Fraction | Whey |
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| Ref Sequence ID | NP_776540.1 |
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| Aminoacid Length | 580 |
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| Molecular Weight | 58092 |
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| FASTA Sequence |
Download |
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| Gene Name | MUC1 |
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| Gene ID | 281333 |
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| Protein Existence Status | Reviewed: Experimental evidence at protein level |
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Secondary Information |
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| Presence in other biological fluids/tissue/cells | mammary, salivary,
lung, pancreas, kidney and stomach |
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| Protein Function | integral membrane component; glycosylated molecule of MUCl on the surface of epithelia
presents a physical barrier protecting the cell; anti-invasion characteristics;roles as a growth inhibitor; at
digestion;protecting membrane proteins from protease action;being a large, extended
membrane protein, it may shield other nearby residents. |
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| Biochemical Properties | rich in serine, threonine,proline, alanine and glycine; rigid, extended molecule due to random coil
promoting properties of prolines and the further rigidity
conferred by glycosylation; beneficial characteristic of MUCl is its relative durability,
especially its resistance to proteases |
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| Significance in milk | MUCl may
be a factor regulating size of MFGs, membrane secretion,
and fat content of milk; sialic acid of mucins on MFGs prevent their clumping and
clogging the ducts through which they must pass |
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| PTMs | glycoprotein; 50% carbohydrate, 30% of which was sialic acid; polymorphic and
carbohydrate portion is of variable nature; serine and
threonine hydroxyls provide sites for glycosylation; human milk MUC1 has high galactose,
modest level of sialic acid, and lack of detectable mannose; bovine MUC1 has less
galactose, significant mannose and much higher sialic acid; galactose
and N-acetylglucosamine are the dominant sugars in the
human mucin; O-linked oligosaccharides
are comprised of a core unit attached to MUCl via
N-acetylgalactosamine, a backbone, and a terminal region; The core and backbone may be branched and the ends may
be terminated by sialic acid, galactose, fucose or N-acetylgalactosamine;
Sulfation may also occur at the periphery; |
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Site(s) of PTM(s)
N-glycosylation,
O-glycosylation,
Phosphorylation
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| Predicted Disorder Regions | 28-359,544-563 |
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| DisProt Annotation | |
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| TM Helix Prediction | 2TMHs; (7-29), (486-508) |
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| Significance of PTMs | The oligosaccharides carry
substantial sialic acid at their termini and this accounts for
two putative functions of this mucin, i.e., to keep ducts and
lumens open by creating a strong negative charge on the
surface of epithelial cells which would repel opposite sides
of a vessel, and to bind certain pathogenic microorganisms; sialic acid content in terminal positions on oligosaccharides
of the mucin confers a negative charge to the
extracellular surface,that might prevent wall to
wall adherence in lumens and ducts thus preventing their
closure and preserving the integrity of secretory systems
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| Bibliography | 1. Patton, S., Huston, G. E., Jenness, R., & Vaucher, Y. (1989). Differences between individuals in high-molecular weight glycoproteins from mammary epithelia of several species. BBA - Biomembranes, 980(3), 333–338. https://doi.org/10.1016/0005-2736(89)90321-0.
2. Schroten, H., Hanisch, F. G., Plogmann, R., Hacker, J., Uhlenbruck, G., Nobis-Bosch, R., & Wahn, V. (1992). Inhibition of adhesion of S-fimbriated Escherichia coli to buccal epithelial cells by human milk fat globule membrane components: a novel aspect of the protective function of mucins in the nonimmunoglobulin fraction. Infection and Immunity, 60(7), 2893–2899. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/1377184.
3. Mather, I. H., & Keenan, T. W. (1975). Studies on the structure of milk fat globule membrane. The Journal of Membrane Biology, 21(1–2), 65–85. https://doi.org/10.1007/bf01941062. |
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